The present invention relates generally to handling equipment and more particularly to equipment for transferring articles through a multi-stage process. Such multi-stage processes may include, for example, the shaping of metal containers, which is generally carried out in a number of stages. The shape of the metal container needs to be gradually reformed through a series of small steps, in order to ensure that the metal is not over-stressed. Thus, processes such as necking or general can shaping are suitable for application of the invention. The invention provides a design of machinery suitable for transferring articles through a multi-stage process. The resultant machinery has a reduced floor footprint compared to conventional equipment.
A multi-stage process may involve about 50 individual stages, each requiring different tooling. As an article moves through a multi-stage process, it needs to be presented to the tooling required for each stage of the process and thus, the machinery utilised for such processes may become very large, taking up a large amount of space on the factory floor. This has disadvantages for both the efficient use of space and also the time required to transport the articles between the tooling used to carry out the various stages of the process.
It has been common practice for over 20 years to replace many in-line conveyor systems with a series of rotating circular turrets, which support a plurality of articles. For example,    U.S. Pat. No. 3,983,729 (NATIONAL CAN CORPORATION). 1976-10-05. describes a method and apparatus for necking and flanging the open end of a cylindrical container, such as a food can. The containers are transported through this multi-stage process, supported on the periphery of a circular turret. U.S. Pat. No. 4,808,053 (HOKKAI CAN COMPANY). 1989-02-28. describes another handling system, in which a barrel and a cover are combined. The apparatus described in this patent again comprises a number of circular turrets upon which the containers (or parts thereof) are transported.    U.S. Pat. No. 5,282,375 (REYNOLDS METAL COMPANY). 1994-02-01. describes a handling system for necking the open end of a metal container body. In this arrangement, the metal container bodies are supported on the periphery of a circular turret by means of suction applied to a series of base pads defining a series of “pockets” around the periphery of the turret.
A disadvantage of these systems is that a large number of circular turrets may be required to complete the multi-stage process and although of reduced size compared to an in-line conveyor system, this may still occupy a significant proportion of a factory's floor space. Therefore, an aim of the present invention is to provide a more compact design of machinery for handling articles through a multi-stage process.